The field of the disclosure relates generally to displaying a condition of a vehicle and, more specifically, to methods and apparatus for indicating an altitude of a vehicle relative to nearby terrain or obstructions.
Navigation charts, whether physical or electronic, are used to plan and track aircraft flights. Some navigations charts include recommended altitude information for predefined routes, such as airways or routes of departure from airports. Furthermore, moving maps are used to depict an aircraft's current position and may include topographical information, such as terrain elevation. Some moving maps color code features within the map based on an altitude of the features relative to an altitude of the aircraft.
Such charts and maps are useful for planning and plotting air travel. However, in an emergency situation, such as a mechanical failure or a load shift, existing systems require an operator to interpret a relatively large amount of information in order to determine a safe altitude or a safe direction of travel, while also addressing the cause of the emergency in a stressful environment. Furthermore, if the emergency occurs off a planned route, the operator may have relatively little information readily available. The operator may therefore spend valuable time collecting and interpreting information or arrive at an incorrect result, presenting a risk of flight into terrain. Accordingly, a need exists for a continuously updated indication of relative altitude in potential directions of travel.